Abstract: The studies focused on the thermal-mechanical behavior under cycle thermal load with a working load are relative little. Based on the laboratory model test method, this study aims to study the heat transfer performance and bearing characteristics of the pile under working load when cycle thermal load is applied. The temperature of pile and surrounding soil, horizontal soil pressure, thermal strain and pile head settlement are measured. The results show that the temperature of pile and surrounding soil varies little; and horizontal soil pressure recovers nearly to initial value after cycling. Moreover, it is also shown that a little residual strain will be produced in the pile, and the settlement will accumulate as the cycle thermal load is applied, so as to influence the bearing characteristics of structure.

Key words: energy pile, cycle thermal load, saturated sand, model test